This invention relates to railway cars and, more particularly, to a hatch cover assembly for a railway hopper car.
Railway cars such as covered hopper railway cars are used to move various types of lading. Such a car typically has a number of hoppers into which lading is loaded through an opening or hatch in the roof of the car. The hatch has a cover and the cover has an associated latching mechanism by which the hatch can be locked in a closed position when the car is moved. The hatch for each hopper is aligned along the center line of the railway car and the hatch is oriented so its opening and closing movement is also the center line of the railway car. Conventionally, and as shown, for example, in U.S. Pat. No. 4,248,160 the latching mechanism for the hatch is mounted on top of the hatch cover and its axis of operation is also along the center line of the car.
The American Association of Railroads (AAR) has established rules and regulations with respect to the design of railway cars such as covered hopper cars. One of the elements covered by these specifications is the height of the car. Included in this specification is not only the height of the car, but also the height of the hatch, hatch cover, and latching mechanism for the hatch cover. If, the height (or profile) of the hatch cover and its associated latching mechanism could be reduced, the roof height of the car could be correspondingly raised; so while the overall height remains within the AAR specifications, the carrying capacity of the car could be substantially increased.